The Royal Museum of Fine Arts was part of the 19th-century expansion of Antwerp’s city centre. The original building had high ceilings and wide spaces, but during the 20th century the museum underwent many haphazard changes: courtyards were covered, windows were closed off, new walls were added and the logical routing of the original whole was disrupted. This intervention aims to reverse this disruption by defining three main functional areas: a public block, the museum including its storage space, and staff and guest rooms. By adding an extension the original routing is restored and allows an integrated exhibition space with six courtyards for the addition of a new ‘vertical’ museum: open ceilings, staircases and elevators for new levels, and double walls for a new independently experienced routing. The interiors have a succession of colours: from the grey-yellow of the vertical museum to the characteristic golden-brown of the Rubens and Van Dyck rooms, and through to the old Pompeiian red of the staircase.